Anybody building and flying this ARF. I am almost done putting one togather. I am putting a YS 120 four stroke engine (NIB) in it. Engine was purchased about 4 years ago. Any advise on the plane and engine will be a big help. This is my first YS engine and I read that they can be hard to tune. Will this plane be hard to land? The only bi-plane that I have flown is a Phanton 90 and it is real easy to take-off and land. Thanks for any help. WayneM.

I have been flying a YS-110 the last 2-1/2 years and It is without a doubt the best glow engine I have ever had. Super reliable idle, great power, it'll swing a 15 x 6 APC @ 9400, de-tune it 300 - 400 RPM's. I've only run Powermaster YS/Saito fuel, 20% - 20%, and it almost looks like you've got smoke on most of the time. It needed very little tunning from the way it came from the factory.

I'm curious about the Cermark Pitts, I' considering getting one and putting a YS-140 in it for power. I've heard there used to problems with material quality (plywood) but I've nerver read any reports on how the plane flys and handles or what it's charicteristics are. I'd love to hear some reports on the plane.

I've got one with a MVVS .91 2str.
flies great
landings are easy but hard to stick (it hops >baloons) because of the bi wing & the light structure
have fun
V.

Thanks for the replys, I hope my engine runs like yours Bgold. I am almost done with the pitts. It is built lite and I had to fit the bottom wing to the fuse. It set with the trailing edge up so the hold down bolts didn't fit. Also the (I) strutts were way off until I sanded down the wing saddle to line up. I am talking lowering the back edge 1/8 inch. After that they fit. I wanted to change the pull-pull elevators, they go to one servo one side is up for both elevators and the other side is down. It will be a while before I fly it,will post results when I do. Wayne

Hi Wayne,

I have the Cermark Pitts and have many flights. It will hop on landing unless you are patient and get the speed just right. I have a Saito 180 and it has plenty of power as you may imagine. I have four aileron servos and it it very responsive. I put about 60% expo in the aileron channel and that smoothed things out a lot. I doesn't take much rudder on takeoff, and if you use too much initally you will then have to chase it a bit. It gets off pretty quick but don't force it off at too low a speed. I used expo in the elevator and rudder but don't remember how much. I added a tailwheel assembly from Troy-built hobbies, and that really makes the ground handling nice. It is responsive and will do most anything. Dead stick landings are over pretty quick as the Pitts has a steep glide angle. let me know if you have specific questions......

Randy

Hi Randy, Thanks for taking the time to help me. Did you use the pull-pull elevator setup that the plans call for? I wanted to use 120 size golden rods, but not enough wood in the back to support them. I went to 4/40 wire and clevis. Do you think the controls setup in the book are about right? My plans call for the CG to be 1/4 in front of the lower wings leading edge. Is that a good starting point? In Bgold's post he said he uses power master 20-20 fuel. Anyone tryed Byron fuel 15% nitro and 20% oil in YS engines? This is what I have been using in my glow engines. I may have to order the 20-20 blend. Wayne

Hi Wayne,

I mounted the rudder and elevator servos in the tail, as shown in the instructions. If I were to do it over again I'd use the two servo cutout/locations in the tail for the elevator, one servo on each elevator half, and put a pull-pull system in for the rudder, and use a 100 plus oz/in servo. Mine came out a little nose heavy due to the Saito 180 and the vibration damping mounts I used. I posted some pictures here at

http://www.rcuniverse.com/forum/m_4661034/tm.htm

I've never had a YS engine, but have heard that they are very powerful for their displacement. I just use Powermaster 15% fuel with the 18% castro/synthetic mix.
I did fly it with the CG as shown on the plans, but ended up adding some tail weight.
It is a pretty responsive model, and will do what you tell it to, whether you meant it or not!

Here is a picture of the rudder linkage. The elevator looks nearly the same on the other side of the fuselage

Randy

Hi Randy, I checked my plane and there is no cut-outs in the tail for servos. In fact there is not much wood back there at all. I used pull-pull on elevator and rudder. Hitec 605s on both, I hope they are strong enough. Wayne

Wayne,

I'm sure they will be fine. I understand the model has been updated several times since it came out in the late 90's. Keep us posted on how the assembly goes and how it flys with that YS engine....

Randy

Will do ,Randy. I will try to post some pictures later. Wayne

I just built and flew my cermark pitts with a g26 RCignition conversion and it is not under powered at all. Take offs are quick and smooth, landings are quick and bouncy. First attempt and I missed the runway, bring em in under power and hold her off til last second, cut power and roll out. I am putting a skywriter smoke system in and am having troubles on the bench. Does the engine need to run to get it pumping?
I blew thru it to prime it, hooked up a 6 volt btty and plugged into chnnl5 on my 9cap and nada, nothing. No pump noises at all. I set the epa on servos all over the place- nada nothing.
this a great flying plane, 2 clicks of left ail and one of down elev and it was hands off for a 1/4 mile.

I need smoke on this so any help is appreciated

Race101

Hi Race101, I am glad that you report a good flyer. I am done with mine but, to windy today to even take pictures to post. Are you flying with the wheel pants on and did you use the pull-pull system on yours? I plan to pick a calm time to maiden my Pitts. I will take care to stay on throttle and hold it off after cutting throttle. Wayne M.

Hey Waynem,
Wheel pants on no pull-pull.
I used HD 4-40 and Giant scale racing servos w/ HD dubro connectors. No slop!!!

I would bring plane in at 1/4 throtle until you are about 6' off the ground and keep holding the elev more and more til you run out(have a high rate on if needed for landing) and you should then be a foot off ground and it will land nicely otherwise you will have bounces to deal with. With the lightened G26 I used I had to add an onuce or two at the rear, which was ok cause I planned to put smoke on it eventually anyway. Let me know how it goes